1. Field of the Invention
The present invention is directed to an adjustable damping valve arrangement having a main stage valve with a main stage valve body which is guided in a damping valve housing so as to be axially moveable.
2. Description of the Related Art
An adjustable damping valve arrangement known from US 2013/263943 A1 comprises a preliminary stage valve and a main stage valve. The main stage valve has a main stage valve body which is guided in a housing so as to be axially movable. The main stage valve body and the housing form a control space for the main stage valve, and the pressure level in the control space is adjusted by the preliminary stage valve. Consequently, the annular gap between the inner wall of the housing and an outer lateral surface of the main stage valve body must be very closely toleranced. While the annular gap can be closed by a seal, it nevertheless requires very precise fabrication.
The main stage valve body has a central axial guide shaft which projects into a through-opening of an intermediate wall and forms the preliminary stage valve with a preliminary stage valve body. The through-opening must also be manufactured in a very precise manner.
The housing has a quantity of radial openings, and damping medium coming from the main stage valve flows through these radial openings. Above the aforementioned intermediate wall, a plurality of radial outlet openings are formed in the housing for the preliminary stage valve.
Radial openings are basically difficult to produce. When produced by cutting, additional difficulties arise in deburring the radially inwardly directed ends of the radial openings. On the whole, the housing turns out to be very difficult to produce.
It is thus an object of the present invention to provide a damping valve arrangement in which the manufacturing problems known from the prior art are overcome.